Combination Sum
Desicription
Given a set of candidate numbers (C) (without duplicates) and a target number (T), find all unique combinations in C where the candidate numbers sums to T.
The same repeated number may be chosen from C unlimited number of times.
Note:
- All numbers (including target) will be positive integers.
- The solution set must not contain duplicate combinations.
For example, given candidate set [2, 3, 6, 7] and target 7,
A solution set is:
代码语言：javascript复制[
[7],
[2, 2, 3]
]Solution
代码语言：javascript复制class Solution {
private:
vector<int> tmp;
vector<vector<int> > res;
public:
vector<vector<int>> combinationSum(vector<int>& candidates, int target) {
sort(candidates.begin(), candidates.end());
dfs(candidates, target, 0);
return res;
}
void dfs(vector<int>& candidates, int target, int index){
if(index == candidates.size())
return ;
int sum = 0;
for(int i = 0; i < tmp.size(); i )
sum = tmp[i];
if(sum == target){
res.push_back(tmp);
return ;
}
else if(sum > target)
return ;
else{
for(int i = index; i < candidates.size(); i ){
tmp.push_back(candidates[i]);
dfs(candidates, target, i);
tmp.pop_back();
}
}
}
};
